Re: [PATCH 1/2] phy: marvell: comphy: Convert internal SMCC firmware return codes to errno

[Andrew Lunn <andrew@lunn.ch>]

On Wed, Sep 02, 2020 at 04:43:43PM +0200, Pali Rohár wrote:
> Driver ->power_on and ->power_off callbacks leaks internal SMCC firmware
> return codes to phy caller. This patch converts SMCC error codes to
> standard linux errno codes. Include file linux/arm-smccc.h already provides
> defines for SMCC error codes, so use them instead of custom driver defines.
> Note that return value is signed 32bit, but stored in unsigned long type
> with zero padding.
> 
> Signed-off-by: Pali Rohár <pali@kernel.org>
> ---
>  drivers/phy/marvell/phy-mvebu-a3700-comphy.c | 14 +++++++++++---
>  drivers/phy/marvell/phy-mvebu-cp110-comphy.c | 14 +++++++++++---
>  2 files changed, 22 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/phy/marvell/phy-mvebu-a3700-comphy.c b/drivers/phy/marvell/phy-mvebu-a3700-comphy.c
> index 1a138be8bd6a..810f25a47632 100644
> --- a/drivers/phy/marvell/phy-mvebu-a3700-comphy.c
> +++ b/drivers/phy/marvell/phy-mvebu-a3700-comphy.c
> @@ -26,7 +26,6 @@
>  #define COMPHY_SIP_POWER_ON			0x82000001
>  #define COMPHY_SIP_POWER_OFF			0x82000002
>  #define COMPHY_SIP_PLL_LOCK			0x82000003
> -#define COMPHY_FW_NOT_SUPPORTED			(-1)
>  
>  #define COMPHY_FW_MODE_SATA			0x1
>  #define COMPHY_FW_MODE_SGMII			0x2
> @@ -112,10 +111,19 @@ static int mvebu_a3700_comphy_smc(unsigned long function, unsigned long lane,
>  				  unsigned long mode)
>  {
>  	struct arm_smccc_res res;
> +	s32 ret;
>  
>  	arm_smccc_smc(function, lane, mode, 0, 0, 0, 0, 0, &res);
> +	ret = res.a0;
>  
> -	return res.a0;

> +	switch (ret) {
> +	case SMCCC_RET_SUCCESS:
> +		return 0;
> +	case SMCCC_RET_NOT_SUPPORTED:
> +		return -EOPNOTSUPP;
> +	default:
> +		return -EINVAL;
> +	}
>  }

Hi Pali

Maybe this should be a global helper translating SMCCC_RET_* into a
standard errno value?

	 Andrew